1. Field of the Invention
The present invention relates to a shielding device applied to electronic devices, and more particularly, to a shielding device that is anti-ESD (electronic discharge) and EMI (electromagnetic interference) blocking.
2. Description of the Prior Art
Electrostatic discharge (ESD) is the sudden and momentary electric current that flows between two objects at different electrical potentials.
One of the causes of ESD events is static electricity. Static electricity is often generated through tribocharging, the separation of electric charges that occurs when two materials are brought into contact and then separated.
Electromagnetic interference (EMI) is a disturbance caused in a radio receiver or other electrical circuit by electromagnetic radiation emitted from an external source. The disturbance after coupling may form common-mode noise that interrupts, obstructs, or otherwise degrades or limits the effective performance of the circuit. The source may be a microprocessor, electrical circuit, ESD or power sources.
A conventional anti-ESD method is usually to set up protection circuits around input/output sites, or to conduct the charges to ground. A conventional method of EMI-blocking is usually to use an EMI shielding material such as springs or a gasket. These conventional methods of preventing ESD and EMI, however, take up space and are expensive.